17.29 Do good smells bring good business, continued.

In Exercise 17.9 (page 317) you examined the effects of a lavender odor on customer behavior in a small restaurant.

Lavender is a relaxing odor. The researchers also looked at the effects of lemon, a stimulating odor. Here are the times in min utes that customers spent in the restaurant when no odor was present:

103 68 79 106 72 121 92 84 72 92 85 69 73 87 109 115 91 84 76 96 107 98 92 107 93 118 87 101 75 86 When a lemon odor was present, customers lingered for these times:

78 104 74 75 112 88 105 97 101 89 88 73 94 63 83 108 91 88 83 106 108 60 96 94 56 90 113 97

(a) Examine both samples. Does it appear that use of twosample t procedures is justified? Do the sample means suggest that a lemon odor changes the average length of stay?

(b) Does a lemon odor influence the length of time customers stay in the restaurant? State hypotheses, carry out a t test, and report your conclusions.